1, 4-bis (2-nitrovinyl) benzene and derivatives thereof as fungicides



United States Patent 1,4-BIS(2-NITROVINYL)BENZENE AND DERIVA- TIVESTHEREOF AS FUNGICIDES William J. Pyne, Painesville, Ohio, assignor'toDiamond Alkali Company, Cleveland, Ohio, a corporation of Delaware a NoDrawing. Filed July 27, 1960, Ser. No; 45,556

,. '20 Claims. (Cl. 167-30) wherein R, R arid R" are the same ordifferent radicals selected from theig-roup consisting of hydrogen,halogen, i.e., fluorine, chlorine, bromine and/or iodine,.chlorine beingpreferred, alkyl radicals, e.g.-, methyl, ethyl, propyl,

liutyl tor the like; and aryl radicals, e.1g., phenyl, jnaphthyL;

or the like; X is halogen, i.e., fluorine, ch1orine,brornine,

and/oriodine, chlorine being @referred, or NO and m+p4.

l Illustrative compounds of this type are the following:

II. 2 nitro-1,4- bis(Z nitmVinyDbenZene ?H=CHNO2 A a novel compoundsalso form 3 ,105"004 Patented Sept. 24, 19632-chloro-5-nitro-1A-bis(2-nitrovlnyl) benzene CH=C H--N 02 OzN CH=CHN O:

VII. 2,3,5-trichloro-1,4-b1s( 2-nitrovlny1)benzene CH=OHN0 a VIII.1,4=-bis (2-bromo2-n1troviny1 benzene CH=C Br-NO 2 IX. 1,3-bis(2-nitroviny1) benzene CH=C H-NQ:

Presently preferred novel compounds of this invention embodied inpesticidal compositions of this invention are those having the followingstructural formula, which a unitary part of this invennon:

Hd-a e wherein X is halogen or nitro, vR is as defined hereinbefore, apreferred compound having at least one R as hydrogen, and a is a numberfrom 1 to 4, inclusive. Prefer-red compounds are those'having thenitriovinyl groups in the 1 and 4 positions. Illustrative novelcompounds of this invention are:

2-chl0ro-1A-bis(2-nitrovinyl)benzene on=o H-NQa 2,5-dlcl1l0r0-1,4-bis2-nitrovinyl)benzene CH=C H-NO 2 CH=CHNO: 2-chloro-5-nltro-1, t-bis2-nitrovinyl benzene CH=CH-NO2 CH=CH-NO2 2,3,5-t1leltlol'o-1,4-bis(2-nitrovinyl)benzene CH=OH-NO2 Cl- Cl In general, compounds of thisinvention, comprising both the novel compounds and the other activecompounds torming a part of the fungicidal compositions of thisinvention, may be formed by reacting an aromatic dialdehyde with aprimary aliphatic nitro compound. For example, the reaction may beillustrated by the following equation:

The reactions involved in preparing aotivecompounds of this inventionadvantageously are carried out in the presence of a basic catalyst.Illustrative and suitable catalysts are primary and secondary loweralkyl amines such as n-butyl amine, ethylamine dimethyl amine, npropylamine, or the like; alkali metal hydroxides, e.g., sodium hydroxide,potassium hydroxide, lithium hydrox ide, or the like; or alkali metalcarbonates such as sodium carbonate, potassium carbonate, lithiumcarbonate, or the like. At present, n-butyl amine is a preferredcatalyst.

Reaction is conveniently carried out by refluxing the reactants in Wateror an organic solvent such as metha 1101 or, if desired, in the absenceof a solvent. Recrystallization of the product can the affected from anysuitable solvent such as nitromethane.

The compounds and compositions of this invention exhibit singularactivity as foliage protectants, e.g., as non-phytotoxie foliagefungicides as well as fungicides generally. A particularly preferredcomposition comprises a minor proportion of 1,4-bis(2-nitrovinyl)benzene and a major proportion of a carrier, whichcomposition exhibits a high degree of fungicidal activity withsubstantially no phytotoxicity, thus comprising an excellent foliagefungicide. It is quite unexpected that such compounds are non-phytotoxicsince mononitro-vinyl compounds generally, e.g., nitroethylenes, tend toburn and/ or destroy plant foliage. In this connection, the leastphytotoxicity of compounds of this invention is seen in theunsubstituted aromatic nucleus (I) and in the chlorinated compounds,e.g., III, VII, and IV.

In order that those skilled in the art may more completely understandthe present invention and the preferred methods by which the same may becarried into effect, the following specific examples may be offered:

EXAMPLE 1 Preparation 0 Z,4-Bis(2-Nitrovinyl)Benzene Part A.-l,4bis(2-nitrovinyl)benzene is prepared by the method of Worrall, OrganicSyntheses, vol. 9, page 66 (seealso Worrall, J.A.C.S. 62, 3253 (1940)).

Terephthalaldehyde (26.8 g., 0.2 mole) and nitromethane (24.4 g., 0.4mole) are dissolved in .100 ml. of methyl alcohol at 10 C. To thissolution is added 16 g. (0.40 mole) of sodium hydroxide dissolved in 50ml. of water. After all the caustic is added, this mixture is pouredinto 200 ml. of dilute (50%) hydrochloric acid; there is isolated 44 g.of a solid melting at 200230 C. This material is recrystallized fromethyl alcohol and there is obtained 17.6 g. (40%) of a yellow solidmelting at 223 C. Preparation of the desired reaction product, C H N Ois indicated through the following elemental analytical data:

Also isolated in this experiment is 1,4-'bis(1-hydroxy-2-nitroethyl)benzene melting rat 178l80 C.

Part B.1,4-bis(2-nitrovinyl)benzene is tested against the fungi whichincite the early blight and late blight diseases of plants using thefollowing procedures:

A tomato foliage disease test is conducted measuring the ability ofl,4-bis(2-nitrovinyl)benzene to protect tomato foliage against infectionby the early blight fungus Alternaria solani. Tomato plants 5 to 7inches high of the variety Bonny Best are employed. The plants aresprayed with ml. of test formulation at concentrations to give at leastthree finite values of disease control with the dosages indicated in thefollowing table of 1,4- bis(Z-nitrovinyDbenzene in combination with 5%acet0r1e--0.01 Triton X-l55and the balance water at 40 lbs. air pressurewhile being rotated on a turntable in a spray hood. After the spraydeposit is dry, the treated plants and comparable untreated controls aresprayed with a spore suspension containing approximately 20,000 conidiaof A. solani per ml. The plants are held in a saturated atmosphere for24 hours at 70 F. to permit spore germination and infection. After 2 to4 days, lesion counts are made on the three uppermost fully expandedleaves. Percent disease control is then calculated by basing it on thenumber of lesions obtained on the control plants.

Fungicidal utility is demonstrated by the ability of the are made on thethree uppermost fully expanded leaves and percent disease control iscalculated. .1

The results of these tests at four rates of chemical application are asfollows:

Percent disease control concentration, p.p.m..

Fungus 12s 64 32 16 p.p.m. p.p.m. p.p.m. p.p.m

Early blight 94 83 73 63 Late blight 99 98 90 77 Part C.Sterile soil isinfested with Rhizoctonia solani grown on a cornmeal-sand medium. Inorder to obtain the desired ino-culum'potential in the test, two 250 ml.flasks containing a 10-day old culture of the fungus are mixed per levelflat of sterile soil. The infested soil is then placed in small Dixiecups (4 oz. squat). Treatment of the soil is accomplished by drenching25 ml. of a test formulation on the surface of; the soil in the cups.The test formulation is prepared by weighing or measuring theappropriate amount of test compound, adding acetone, then emulsifier andbrought to volume with distilled water. -The final. concentrations areacetone and 0.01% Triton X-155 by volume. When dilutions are made inthis testthe concentration of the emulsifier and acetone, aremaintained. The amount of 1,4-'bis(2 -nit rovinyl) be nziene employed isequivalent to 64 and 32 lbs./ acre. The surface area of the soil in thecups is 5.73 square inches so that it requires 0.414 mg. of testchemical per cup to achieve a rate'of 1 lb./ acre. After drenching, thecups are placed in a saturated atmosphereat 70 F. for 48 hours. 1 At theend of this time, the fungus mycelinrn has completely overgrown thesurface of the soil in'the control cups. The effectiveness of the testchemical is determined by observing the cupsiand grading them on a scalefrom 0=oomplete inhibition of growth to =growth equivalent to that atthe control. These grades are then expressed as percent control, 0indicating no activity] and 100% indicating complete inhibition ofmycelial growth over the soilysurface.) Using this procedure, at a rateof 64 lbs/acre. and 32 lbs/acre 1,4-bis(2-nitrovinyl)benzene exhibits60% land 20%control, respectively.

, EXAMPLE 2 Preparation of. 2-Chl0ro-1,4-Bis(Z-Nitroyinyl)Benzene PartA.-5 25 g. of 24ch1oro-p-xylylene dichloride is dis solved in a solutioncomprising 450 g. of anhydrous sodium carbonate and 6 liters ofgwater.The mixture is then refluxed with stirring in a flask for about 8 hours,preferably until reaction completion. About 4 liters. of .water is thenremoved 1 through distillation, the residue removed from the container,cooled to about 5 and filtered, yielding the desired diol. The productis then recrystallized 6 melting at 175 C. Analysis indicates formationof the desired 2-chloro-1,4-bis 2-nitroviny1 benzene Part B.The fabricpreservation test measures the ability of test compounds to preventdeterioration of cotton duck in soil known to be infested with cellulosedecomposing organisms. Duplicate strips of 8 oz. cotton duck 1" x 6",with the long dimension parallel to the warp, are treated by dippingthem into a one percent solution ofZ-chloro-1,4-bis(2-nitroviny1)benzene dissolved in acetone. Each stripis dippcd'in solution for 10 seconds then allowed to drain untildripping stops. They [are then placed on a paper towel until dry andthen planted vertically in a wooden box 12'" x 12" x 8" deep containingsoil infested with cellulose destroying fungi. Checks are also includedin the test box which is thenincubated at 80 F. for two weeks. At theend of the exposure period, the test'specimens are removed firom thesoil bed and if not completely degraded are gently washed to removesoil, dried, and breaking strength determinations made on tensilorneter.It is observed that an 85-lb. tensile strength is retained after 14 daysburial as compared to -an untreated buried control of 0 lb. and anunburied, un-

Preparation of a Chlor0-Nitr0-1,4Bis (2-Nitrovinyl)Benzene mole) isadded in small portions to 125 ml. of turning nitric acid at 10 C. Afterall the solid has been added, the mixture is stirred for an additionalhour. The solution is then poured on ice and a yellow solid settles out.

' T hissolid is filtered, dried, and recrystallized from 95% from aminimum amount of water. (about 1500 ml.) using decolorizing carbon toremove any color. This yields the 0.2 mole of 2-chloroterephthalaldehyde(MP. -7 6 methane and 1 g. of n-butylamine by heatinglat reflux ton--four hours on a steam bath. The reaction mixture is then cooled,filtered, and the solid recrystallized from nitromethane. A 35.2% pureyield is obtained, the material ethyl alcohol; there is isolated 18 g.(55%) of a yellow sol-1d meltingat 185 C., which is achloro-nitro-1,4-bis (2-nitrj ovinyl)benz"ene.

Element Percent Percent calculated actual EXAMPLE 4 Preparation of2,5-Dichloro-l,4-Bis(Z-Nitr0vinyl) Benzene Using the procedure of theforegoing example, 0.2 mole of 2,S-dichloroterephthalaldehyde (PauliRuggli et al., Helv. Chem. Acta, 27, pages 274-291 (1944)), prepared byheating a,-a,a',af-tetrabromo-2,S-dichloro-pxylene with H for 3 hours at-130 C., is reacted with 0.4 mole of nitromethane and l g. of:n-butyla-mine. This mixture is refluxed on a Water bath for two hoursand the reactionmixtnre cooled, filtered, and the solid recrystallizedfrom nit'romethane. The desired conr- .pound is obtained in a pure yieldof 19% and melts at 260 C. Chemical analysis indicates the (formation ofthe desired Cml-I Cl N O and is as follows:

EXAMPLE festans) the following data, comprising calculations of percentdisease control based on the number of lesions on the test plants andcontrol plants, are obtained:

Part A.Using the procedure of the foregoing two 5 P c t d t 1 texamples, 0.2 mole of 2,3,5-tr1chloroterephthalaldehyde 3235911133333512? (German Patent 360,414), prepared by heating Fungus a,a,a,a',2,3,5heptachloro-p-xylene in H 50 at 9095 512 256 128 C. until evolution ofHCl ceases, is reacted with 0.4 mole of nitromethane and 1 g. ofn-Ibutylamine. The mixture l laily bli z t 98 90 52 is refluxed on aWater bath for four hours and the reaca e 100 94 82 tion mixture is thencooled, filtered, and the solid recrystallized from :nitromethane. Thereis thus obtained a the data f 3 90% yield Of the desired product melting32350 C v1nyl)benzene CXhl'bltS an excellent fungicidal activityChemical analysis indicates formation of the desired agamst bothearlyand late blight fungus- C H CI N O4 and is as follows: EXAMPLE 6Using the procedure of Example 1, Part B, 1,4 bis(2- Element jfiflig gg232 bromo-2-nitrovinyl)benzene, at dosages of 2000 ppm. and 400 p.p.m.,respectively, gives 99% and 78% control 37,1 of late blight fungus. H 1.1.8

EXAMPLE 7 Part B. Using 2,3,5-trichloro-1,4-bis(2-nitrovinyl) olllustnate the singular lack of phytotoxicity of the benzene in the testprocedures of Exampla 1, Part B, to 2 fungmdal d1n1 trov1ny1COIIIPOUIIdS Of this il'lVGIlllOIl, 3. protect tomato f li g i i f i bth early 3 senes of expernnents are carried out wherein such comblightfungus (Alternaria solani) with tomato plantspounds,laswellasseveralmononitrovinylwmpounds,are (variety Bonny Best) 5to 7 inches high, and against inapplied to the folrage of several testplants. The results, fection by the late blight fungus (Phytophthominindexed comparatively, are as follows:

Phytotoxiclty (0=no lnjury11=plant kill) Compound Concentraon TomatoBean Corn Outs (mum) O2NCH=CH-CH=CHNO2 4,800 0 o 0 0 OzNCH=OH-CH=CH-N0z4,800 a 1 0 0 l lo;

0zN-GH=CH-CH=CHNO1 4,800 0 0 0 0 01 I .OzN-CH=CH-CII=CHNO2 2,400 0 0 0 001 IITO: OzNOH=CH-CH=CHNO1 4,800 0 0 0 0 C1 o2NoH=0H--o11=om-N0, 4,800 00 0 w 0 OgNCB1'=CH-CH=CBr-NO2 2,400 0 0 1 o Mononitrovinyl CompoundsOzN-CH=CHCI -1 2,400 10 s a 01NCH=OH 4, s00 11 11 11 s Y 2, 400 11 9 5 3As the foregoing data clearly indicate, the compounds of this inventionare characterized by an absence of phytotoxicity, while mononitrovinylcompounds exhibit substantial phytotoxicity.

It is to be understood that although the invention has been describedwith specific referenw to particular embodiments thereof, it is not tobe so limited, since changes and alterations therein may he made whichare within the full intended scope of this invention as defined lay theappended claims.

What is claimed is:

1. A non-phytotoxic, fungicidal composition comprising a majorproportion of a finely-divided liquid or solid carrier, a minor amountof a surface active agent and a fungicidal amount of a compound havingthe structure:

wherein R and R are selected from the group consisting of hydrogen,halogen and hydrocarbon radicals; X is selected from the groupconsisting of halogen and NO and m+p=4.

2. The method of killing fungi which comprises applying thereto afungicidal amount of a non-phytotoxic compound having the structure:

wherein R, R and R" are selected trom the group consisting of hydrogen,-halogen, alkyl and eryl radicals; X is selected from the groupconsisting of halogen and -NO and m+p=4.

3. The method according to claim 2 wherein the compound is1,4-bis(Z-nitrovinyDhenzene.

4. The method according to claim 2 wherein the compound is2-nitro-1,4-bis(2-nitrovinyl)benzene.

5. The method according to claim 2 wherein the compound is2-ch1oro-1,4-bis(Z-nitrovinybhenzenc.

6. The method according to claim 2 wherein the compound is2,5-dichloro-1,4 bis(Z-nitrovinyDhenzene.

7. The method according to claim 2 wherein the compound ischloronitro-1,4 bis(2-nitrovinyl)henzene.

8. The method according to claim 2 wherein the compound is2,3,5-trich1o-ro-1,4-bis(Z-nitrovinyDhenzehe.

9. The method according to claim 2 wherein R, R and R" are hydrogen, andX is halogen.

. 10. The method according to claim 2 wherein R, R and R are hydrogen,and X is --NO;,,

10 11. The method of killing fungi which comprises applying thereto afungicidal amount of a compound having the formula:

R Xm

lected from the group consisting of halogen and NO 12. The method ofprotecting plant foliage frorn diseases which comprises contacting plant foliage with a fungicidal amount of 1,4-bis-(Z-nitrovinyhbenzene.

13. Compound-s having the structure:

l C-NO:

wherein R, R and R" are selected from the group consisting of hydrogen,halogen, alkyl' and raryl radicals; X is selected from the groupconsisting of halogen and NO and m+p=4, with the proviso that at leastone of X and R is halogen.

14. Compounds having the :formula:

on=o'-Noa References Cited in the file of this patent UNITED STATESPATENTS OTHER REFERENCES Chemical Abstracts: 34: 6625 6625' (1940); 35:84 (1941).

1. A NON-PHYTOTOXIC, FUNGICIDAL COMPOSITION COMPRISING A MAJORPROPORTION OF A FINELY-DIVIDED LIQUID OR SOLID CARRIER, A MINOR AMOUNTIOF A SURFACE ACTIVE AGENT AND A FUNGICIDAL AMOUNT OF A COMPOUND HAVINGTHE STRUCTURE:-